Device for photographic reproduction



Feb. 26, 1957 w. LIMBERGER 2,783,015

DEVICE FOR PHOTOGRAPHIC REPRODUCTION Filed Aug. 1, 1951 @KW F flvyzwrox W54 75 L magzeas By 7 J a %TTORNE Y S United States Patent DEVICE FOR PHOTOGRAPHIC REPRODUCTION Walter Limberger, Hamburg, Germany, assi'gnor to Messrs. Dr. Biiger K. G., Hamburg, Western Germany Application August 1, 1951, Serial No. 239,701 Claims priority, application Germany August 12 1950 2 Claims. (Cl. 248-363) The present invention relates to an arrangement for projecting design and fabricating data on to a piece of work, especially on sheet metal plates, by means of a picture carrier produced by photography, which represents on a reduced scale a workshop drawing made indirectly. or directly by hand, and which is magnified to a high degree by means of a projection device. The arrangement according to the invention is particularly suited for marking-out ship plates, which may have a length of 10 meters or even more and which have to be marked-out to within a tolerance of only few millimeters. However, the invention may also be advantageously applied for marking-out of parts for structural works, e. g. parts of bridges, girders, cross beams, machine parts, and the like.

The present invention relates to an arrangement for projecting design and fabricating data of the kind above described, wherein the workshop drawing is fastened to a drawing support consisting of a number of adjustable supporting elements, which are adapted to be adjusted to form an even and smooth drawing supporting surface and which are provided with means for adjusting and fixing the drawing supporting surface exactly perpendicular to the optical axis of a camera.

The invention relates to a drawing support and provides that the supporting surface for the drawing is mounted in a frame of a casing and is adapted to be adjusted in respect to said frame at a great numberof points in such a manner that the supporting surface for the drawing is exactly level. It is particularly proposed that within that frame a partial vacuum is produced by means of one or more pumps, and that a spider-like reinforcing structure is mounted in the frame, to which the drawing supporting surface is adjustably attached at a great number of points. The invention still further is to be seen in that the surface forming the drawing support is provided with suction openings and is supported by angle irons extending between the side walls of the frame and that adjusting means are provided at the cross points between the angle irons and said arms of the reinforcing member which extend radially from the centre of the drawing supporting device. The ad justing means at the cross points between the radial arms and the angle irons may be constituted by screws engaged by two adjusting nuts. The said screws, which are fixed to the angle irons, may be surrounded by saddle clamps fastened to the radial arms. In addition the invention comprises reducing vthe cross-section of the radial arms in the direction from the centre to the side walls of the frame and providing the radial arms with holes in order to reduce their weight still further.

In order that the invention may be clearly understood and readily carried into practice, all features essential for the embodiment of the invention will now be described in more detail by way of example with reference to the accompanying drawings, wherein:

Figure 1 is a perspective view of the drawing support, viewed from the back and partly broken off;

2,783,016 Patented Feb. 26, 1957 Ice Figure 2 is an enlarged view of part of Figure 1 within the plate holder of the camera.

The drawing support consists of a frame 97 provided with a spider-like stiffening member 98 comprising stitfening arms 100, which extend like rays from the centre 99, have a cross-section decreasing towards their outer ends and they serve for the support of angle irons 101 which carry a perforated suction plate102. In this way it is possible to make the suction plate exactly even, so that it is particularly well suited for the support of the workshop drawing when it is to be photographed. The suction effect is produced by one or more pumps (not shown). Every cross point between the radial arms 100 and the angle irons 101 is provided with an adjusting device, shown on an enlarged scale in Figure 2, for the accurate adjustment of a supporting face or plate 102. These adjusting devices are arranged on the suction wall 102 of the drawing-support, regularly spaced from one another, and are independently adjustable and consist substantially of a bolt 104, with two nuts 105, and a saddle-clamp 106. Each bolt 104 is held in its respective saddle-clamp 106 in such a Way that the latter stands with its saddle between both nuts 105. Each bolt 104 is fastened to the suction wall 102 of the drawing-support on an angle iron part 101, for instance by means of screws 101a, while each saddle-clamp 106 is secured on the radial arms 100 by means of screws 107. The bolts 104 are blocked in their saddle 106 by their nuts 105, so that the suction wall 102 in its working position is solid with the arms 100. If one of the nuts 105 of the adjusting device, say for instance the nut 105, that is near the free end of the bolt 104, is released, then the opposite nut, that is near the fixed end of the bolt 104, enables the bolt 104 to be thrust away from the frame in respect to the saddle-clamp 106, whereby part 101 is adjusted in a direction transversely of the sheet and about normal to the sheet, so that the suction wall 102, following this change of position, is flexed outwardly. After setting the plane or curvature of the suction wall in the required position, the locking nut 105 is tightened again, so that this shape is firmly established. This shaping process of the suction wall can naturally be carried out also in the opposite direction, that is inwardly.

What we claim is:

1. In a suction operated apparatus for projecting design and fabricating data from a drawing upon a piece of work to be fabricated the provision of a device comprising a perforated supporting plate for the drawing Which plate is capable of being flexed to required shapes, a casing frame covered on one side by said plate, means for producing a partial vacuum in said frame, a plurality of separate supporting elements engaging the plate on the side within the frame, a stiffening member within the frame and comprising rigid arms radiating from a central point where they are connected together, and a plurality of independently adjustable devices carried by each arm and spaced along the arm between the arm and an adjacent supporting element and supporting the element; each of said adjustable devices including a part fixed to the plate, a part fixed to the arm and means for adjusting said parts separately in a direction normal to the plate for flexing the plate to required shape.

2. In a suction operated apparatus for projecting design and fabricating data from a drawing upon a piece of work to be fabricated the provision of a device comprising a perforated supporting plate for the drawing which plate is capable of being flexed to required shapes, a rectangular casing frame covered on one side by said plate, means for producing a partial vacuum in said frame, a. series of bars within the frame extending across the frame and serving to support said plate, a spider-like 3 4 stiffening member withinthe frame having its arms cross- 1,895,654 Forrest Jan. 31, 1933 ing said bars, and a plurality of independently adjust- 1,9 5,481 Dilkes Ian. 30, 1934 able screw operated devices carried by each arm of said 2,113,309 Murray Apr. 5, 1938 stiffening member and engaging said bars where they 2,191,036 Seymour Feb. 20, 1940 cross said arms; each of said screw operated devices 5 2,229,760 Mueller Ian. 28, 1941 including a bolt fixed to the plate and adjustably carry- 2,229,761 Mueller Jan. 28, 1941 ing a saddle clamp fixed to the arms, and means in con- 2,263,337 Kamborian Nov. 18, 1941 junction with said boltforflexibly adjusting said plate to 2,324,842 b July 20, 1943 q d p 1 2,372,767 Crouse Apr. 3, 1945 30 2,378,933 Kiemrn June 26, 1945 References Cited in the file of this patent 2,383,161 Pratt Aug 21 1945 UNITED STATES PATENTS 2,405,090 Crouse 2 July 30, 1946 1,198,403 Bagnall Sept. 19, 1916 2,420,316 H1116 May 13, 1947 1,552,817 Boedicker, Sept. 8, 1925 15 2,431,612 Furnas 1947 1,714,589 Chouinard May 28, 1929 9,713 Kemeth Sept. 21, 1943 1,716,322 Proctor June 4, 1929 7 Walker May 9, 1950 1,787,662 Boedicker Ian, 6, 1931 7 ZOb1 June 5, 1951 

